1. Filed of the Invention
The present invention relates to a set of iron golf clubs.
2. Prior Art
A set of iron golf clubs is, for example, a set of a plurality of golf clubs, from a long iron or the 1st iron through a short iron or the 9th iron, a pitching wedge or sandwedge. The respective dimensional elements of these clubs are different, depending on their predetermined settings. First, a shaft gets shorter as its club number increases, accompanied by the weight of a club head getting heavier. Further, a loft angle, i.e., an angle of a vertical plane to a face of a club head increases as the club number gets larger. Further, the larger the club number is, the greater a lie angle, i.e., an angle of a horizontal plane to a shaft, becomes.
Conventionally, to aim at adjusting the weight distribution of a club head, it has been proposed, for example in Japanese Utility Model Application Unexamined Publication No.58-86157, to provide a balance weight at the rear side of a head body, said balance weight being made of a material denser than that of a head body. Further, to obtain a characteristic suitable for each club number, the weight and mounting position of a balance weight have been changed in the past, corresponding to each club number. According to such conventional art, when changing the weight of a balance weight for each club number, the size of the balance weight has been changed, without changing the material thereof. In other words, a specific balance weight exclusively used for a particular club number of a golf club, such as for use with the 3rd iron, the 4th iron and etc., has been manufactured.
However, if the size of a balance weight must be changed per each club number, then eleven kinds of balance weights in total are necessary, from the 1st iron through a sandwedge, which in turn means that eleven kinds of dies or molds for forging or casting also are necessary to manufacture the respective balance weights by forging or casting, so that it results in a higher cost and a more space needed for installing a manufacturing system. Moreover, if the size and shape of a balance weight vary from one club number to another, the design harmony as a set of iron golf clubs will be impaired.